Wednesday 3 March 2021

Hunting the sixth man


The hunt for the sixth person who tested positive for the Brazil variant has been turned into something of a drama. One day, perhaps they’ll turn it into a film pitting the scientists, statisticians and politicians against a deadly virus carried by one unwitting member of the public who returned an anonymous positive test for analysis. To keep it simple, the plot will revolve solely around tracking down the infamous six, ignoring the wider pandemic raging at the time. For added drama, the film version will differ from reality by having the scientists’ hunt obstructed and complicated by a bumbling politician who insists that there isn’t a problem and that if there is it’s nothing to do with him. On second thoughts, that last bit might not require any great feat of imagination at all.

It is all a bit of a diversion, though, which ignores a few key facts. The first of those is that there aren’t only six people in the UK with the Brazil variant. What we know is that, of those who have tested positive for Covid and whose samples have been subjected to genome sequencing, there are six identified cases of the variant. But that sentence includes two significant filters. The first is that not everyone suffers symptoms and even amongst those who do, if the symptoms are minor, there’s no guarantee that they will be tested at all. There will be people in these categories who have the Brazil variant and who are wandering around in complete ignorance of the fact. The second is that, even amongst the positive tests carried out, not all the genomes are sequenced. As at December last year, the proportion of tests being genome sequenced was around 10% (meaning that which variant was being carried by the other 90% was unknown). With the number of positive tests having fallen rapidly since then, the proportion being sequenced will have risen (it’s a capacity issue not a percentage one), but it’s still not 100%.

So, there is still some way to go before we can be certain that we are identifying anywhere near 100% of the cases of any new variant of concern. In the meantime there are two things that could be done to lessen the risk. The first of those is to reduce the extent to which the virus is circulating within the UK – the smaller the pool, the lower the likelihood of dangerous mutations. The second is to prevent new versions being imported by people entering the country. On the first, government policy is, however they attempt to spin it, tantamount to vaccinating the vulnerable as rapidly as possible and then reopening the economy whilst the remainder are still being vaccinated. This is a recipe for leaving a significant pool of virus in the economy for several months to come. It’s a gamble, and not necessarily a carefully calculated one. On the second, government policy is to quarantine only around 1% of those entering the country, and only those arriving directly from only some of the countries where the new virus has been detected. All other arrivals are allowed to leave airports and get onto public transport, and then trusted to self-isolate on arrival at their final destination (a trust which we know to be completely misplaced) whilst the PM regularly stands up in Parliament and repeats the outright lie that the UK system of border controls for Covid is one of the tightest in the world.

Those writing the screenplay will have little difficulty mocking the politicians whilst making the scientists look good. They might, though, struggle to find a way of engineering that essential happy ending where thousands of extra and unnecessary early deaths are prevented. However, Hollywood is like the current PM in one key respect – truth will never be allowed to get in the way of a good story. It just means that the final screenplay may need to rewrite the reality of the next few months.

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